I am hoping that some of you have a bunch of old valve spring retainers lying around.  If you could do a close-up visual inspection it would be a big help.  Or if your engine is handy and easy to access, if you could take a peek through the valve covers.  I would really appreciate your help.

I was getting ready to start reassembling my engine and did a close visual inspection of my valve spring retainers.  These retainers were brand new about 1000 miles ago.  I did not modify them.  They were installed with high performance RD valve springs.  From a few feet away they looked pristine, but when I got the old eyeballs a little closer I noticed what appeared to be fretting.

The retainers look pretty funky, like they could possibly be sintered metal.  Anyone know how to tell if an item is manufactured from sintered metal?  Awhile back I machined four of these things and they behaved like case hardened material.  The surface seemed hard and crusty but once I broke through the case it was very easy to cut.

I have other retainers that do not have the weird fretting appearance.  This one is from a used head I bought on eBay, year & mileage unknown.  It looks rough and porous, but it doesn't have the fretted look.

I figured I could get the reassembly back on track by using the stock retainers that are on my box-stock head.  That head only has a little over 3000 miles on it.  I pulled it down and took a look, same weird fretted appearance.

If you have access to some used retainers (or new ones), please take a close look at them and LMK if they look similar to the photos I have posted here.  I'm dead in the water (DIW) until I can come up with a solution.  I guess it's possible the retainers looked like this when they were new, but I think I would have noticed.  I'm getting old and clearly not as sharp as I once was.

Thanks, Mike

Bottom - exhaust retainers on left.

I ordered and received a set of new retainers.  It took a while, they were on back order.  I see identical defects on the brand new, never used retainers.  

I have to assume this is a normal condition, but it certainly isn't something I want to run in a performance application.  I have no idea how Suzuki makes these things, but these craters and divots are simply cracks waiting to propagate and fail.  I'm glad I found a way to install the RD titanium retainers.

One thing seems to be consistent, older stock retainers don't have the defects.  The defects seem to be confined to newer retainers.  Something changed in their manufacturing process.

Here's a shot of a brand-new, never-used retainer.  Right out of the OEM plastic bag.

That is something I have been contemplating.  I would slice it in half, then polish the cross section.  That will remove any smeared metal.  Best I could do then is examine at 10X. One of these days when I feel real energetic I will give it a try.  Need to pick up some quality hacksaw blades.

I believe the correct way to do it is to polish and then etch with acid.  I suppose a little research is on order.  If I ever do it I will update this post.

You gotta admit, those are some butt-ugly defects.

Hey Versy, what's the back story on your guy?  Is he a metallurgist or materials engineer?  Does he do the cut or should I cut it myself before sending?  I really would like to learn more about these stock retainers.

Ive heard
Don't fret about it. The only fret I ever knew of was on a guitar. NOW I know what
fretting is, and why its inadvisable to do it.
But, in a harsh enough environment, fretting might be unavoidable, unless harder materials get involoved,,
Or what? What solutions exist to solve that?